An exhaust gas aftertreatment system of this type is described, for example, in European Patent EP 1 054 722 B1. This system provides a method and a device, wherein the pollutant-containing exhaust gas of a Diesel engine is initially introduced into an oxidation catalyst to convert NO contained in the gas stream to NO2, and to increase the NO2-content in the gas stream. Subsequently, the gas stream is introduced into a particulate filter to remove, in particular, soot from the exhaust gas. Then, the gas stream is fed into an SCR catalyst to reduce the NOx in the exhaust gas. In addition, cooling devices may be disposed in the exhaust treatment train, in particular upstream of the SCR catalyst. This system is complex in design and requires a not insignificant amount of installation space because the individual components are arranged in series one behind the other.